This invention relates to tube loading apparatus and particularly to the loading of small diameter tubes into correspondingly sized apertures in plate and baffle elements, as for example in the assembly of compact, light weight, high performance heat exchangers in which the tubes are subsequently fixed to accommodating header plates in a brazing or like operation.
It has been known heretofore mechanically to load tubes into a tubular heat exchanger, but this has been in conjunction with relatively large size tubes accommodated in header plates with relatively large clearance. A prior art machine is large and complex and is especially constructed and designed for its intended use and provides a support table which attempts to incorporate in itself the compound movement needed to load successive, relatively off-set, rows of tubes. Further, in trying simultaneously to load an entire row of tubes at a time, the prior art machine substantially excludes itself from that which is possible of attainment in dealing with high density, light weight heat exchangers. In this latter branch of the heat exchanger art, therefore, it has been the practice to load or install tubes as a hand operation. While costly, the hand operation obviates mishaps and errors which can lead to excessive scrapping of parts and materials, and avoids the necessity of building or purchasing the relatively complex machinery available in the prior art. In a brazed heat exchanger, moreover, minimal clearance is permissible between the tubes and aperture walls in which the tubes are received since these joints must be sealed by flowing braze alloy. The luxury of wide clearances at these joints, which would greatly simplify assembly, is not available.